BOISE, Idaho — Idaho Gov. Dirk Kempthorne has met with California Gov. Arnold Schwarzenegger in an effort to exempt French fries from a California list of foods requiring warnings that they could cause cancer.

California is revising a citizens right-to-know law passed in 1986 and will likely include specific warnings about food-based acrylamide.

The chemical was previously considered an industrial agent until a 2002 study reported that it occurred naturally in many carbohydrate-rich foods. It occurs in cereals, for instance, though high levels in potatoes have been a focus, scientists said. It is released when the food is baked or fried.

Studies have linked acrylamide to cancer in animals, according to the World Health Organization, and McDonald's and Burger King have been sued in California for not providing warning labels about their fries.

Some consumer advocates said Kempthorne is misguided, arguing he should be lobbying the food industry to slash levels of the chemical. But Kempthorne wants potatoes — Idaho's No. 1 agricultural product, accounting for $2 billion of the state's economy — off the table in the law's revision. He is concerned that certain changes could stoke fear among consumers and dent potato sales already hurt by low-carbohydrate-diet trends.

"It could have negative economic impact on interstate commerce," said Mike Journee, a Kempthorne aide. "How are you going to get away from something that's naturally occurring?"

The U.S. Food and Drug Administration is assessing the chemical in food, according to a statement on its Web site.

Kempthorne was accompanied by numerous state officials at the May 9 meetings in Sacramento, Calif., including Pat Takasugi, Idaho's Agriculture Department director; Commerce director Roger Madsen; and Toni Hardesty, who heads the Department of Environmental Quality.

In a measure backed by Kempthorne, potatoes and other foods would be exempt from warnings if it could be shown that acrylamide was formed solely from the foods' natural makeup and was released as a result of being cooked, and if producers did everything possible to cut the chemical to the lowest possible level.

Should California's 35.4 million consumers sour on French fries because of cancer fears, potato industries in Oregon and Washington also would take a hit, industry officials warned.

Carol Monahan is chief counsel at the California Office of Environmental Health Hazard Assessment, the agency that enforces the food-warning law known as Proposition 65.

She said it forbids businesses from knowingly and intentionally exposing people to chemicals on a list of known carcinogens or toxins that can cause birth defects.

A 2002 Swedish National Food Authority study first reported that acrylamide occurred naturally in some starch-rich foods as a result of cooking or heat processing. Until then, the chemical was generally thought of as an industrial agent, used in food packaging and to treat sewage, according to the U.S. Department of Health and Human Services.

The Swedish study provided the impetus for reviewing the law, Monahan said, saying the effort may take until next April to complete. It likely won't require warning labels on packages, opting instead for cautionary signs in restaurants and stores.

The agency was partially prompted to review the issue when a lawsuit was filed in Los Angeles County Superior Court in September 2002 against McDonald's and Burger King.

Rafael Metzger, a Long Beach, Calif., lawyer representing the Council for Education and Research on Toxics, said the fast-food restaurants hid that their French fries "contained a cancer-causing chemical."

"Acrylamide is an industrial carcinogen, and it's a major component of the diets of children who eat McDonald's and Burger King French fries," Metzger said.

He declined to identify his clients and said the case has been stayed until at least August.

McDonald's said the lawsuit is without merit, spokeswoman Lisa Howard said yesterday.

A call for comment to Burger King was not immediately returned.

Some consumer-health advocates said Kempthorne, in lobbying Schwarzenegger to get fries exempted, is kowtowing to economic interests at the expense of public health.

"The governors are watching out more for the potato industry than for the consumer, and that's unfortunate," said Michael Jacobson, executive director of the Center for Science in the Public Interest.

Industry advocates countered that science hasn't proved a link to human cancers and that state-by-state efforts to require warnings could create chaos. They also said people have been eating potatoes since about 750 B.C. in South America, and French-fried potatoes since at least the 1830s, when French and Belgium diners popularized the preparation style, according to "The Secret History of French Fries."